All references are based on the 2014 edition of the NEC.
This Service Needs Servicing
According to Argyropoulos, “This service feeds a dwelling as well as a large mechanic’s shop where they do welding, tire replacements, etc. The female cord end sticking out of the disconnect box is the generator hookup. There is a suicide cord that the generator installer made for the hookup.”
Backfeeding an attachment plug in this manner is a violation of Sec. 406.7(B). Prongs of attachment plugs must not be energized unless inserted into an energized receptacle or cord connector.
“The issue I was called out for is that the generator breaker tripped every time they tried to connect it to power the house,” explains Argyropoulos. “I’d say the linemen were very lucky it did.” Section 702.5 requires transfer equipment to be used for this generator hookup.
Mauled at the Mall
According to McElroy, “This is a 3-phase non-fused disconnect. Only three conductors where used, but all six were live. There was no ground anywhere, and they had filled the EMT conduit with silicone. This also made the disconnect no longer waterproof.”
Section 300.18(A) requires raceways to be installed complete between outlets, junctions, or splicing points. This raceway was obviously not quite complete before this installation was made. Because this raceway came up a little short — and it was being used for equipment grounding purposes — it has compromised the continuity of the equipment grounding conductor. Section 300.10 requires metal raceways and metallic enclosures to be metallically joined together into one continuous electrical conductor and shall be connected in a manner to provide effective electrical continuity.
I also question whether there is enough space for all those wires crammed into the left side of the enclosure. Section 312.8 sets a limit for conductor fill to a maximum 40% of the cross-sectional area. This disconnect may be overcrowded.